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 # ollie Architecture
 ## Philosophy
-ollie's design philosophy is Emacs: a small, extensible core. The Go runtime (`agent.Agent`) defines what an agent *is* — an event loop, a backend connection, a message history, and three built-in primitives (`shell`, tool registry, skill registry). Everything else — orchestration, scheduling, workflows, UIs — is pushed out to the surrounding environment.
+ollie's design philosophy is Plan 9 / Acme / Unix: a small substrate that integrates with the surrounding system rather than trying to do everything itself. The Go runtime (`agent.Agent`) defines what an agent *is* — an event loop, a backend connection, a message history, and three built-in primitives (`shell`, tool registry, skill registry). Everything else — orchestration, scheduling, workflows, UIs — is pushed out to external tools, scripts, and frontends.
+
+The key difference from the Emacs model: Emacs extensibility means building capabilities *on top of* its Lisp interpreter and text primitives. Ollie's extensibility means **not** building capabilities into the core at all — instead, the core provides integration surfaces (9P filesystem, shell execution) and lets the surrounding system handle everything else. This is the Acme approach: a lightweight framework that delegates to external programs via a shared filesystem namespace.
 The primary integration philosophy is Plan 9's "everything is a file." `olliesrv` exposes agent state and behaviors as files in a 9P namespace. Any program that can read and write files can drive an agent: shell scripts, editors, web apps, cron, containers.
 All clients communicate via 9P exclusively. Desktop notifications use D-Bus directly (org.freedesktop.Notifications) for elevation prompts only — this is the last remaining D-Bus dependency.
 Design principles: